Statistical analysis
IBM SPSS statistics package was used for statistical analysis. Numerical
data were tested for normality using the Shapiro-Wilk test. Numerical
variables were expressed as mean ± standard deviation. Categorical
variables were expressed in percentages. Paired and unpaired t tests
were used when appropriate. Categorical variables were compared between
groups by using chi square test. The significance level was defined as
p< 0.05. To evaluate interobserver concordance, the
intraclass correlation coefficient was calculated.